This invention generally relates to hybrid automotive control systems, and more particularly to such systems permitting driver manual control of the vehicle but providing automatic override of certain functions of control of the vehicle as is necessary to comply with traffic laws and to compensate for various external conditions of danger.
With over 220 million automobiles in use in the U.S., and more being added daily, it has become essential to provide some degree of limited override over complete manual control of the vehicles by drivers to insure compliance with the traffic laws, and to protect drivers and passengers from various dangerous conditions, such as adverse weather, driver error and fault, adverse road conditions, and improperly driven other vehicles. Adverse weather conditions such as ice, rain, sleet, snow, and fog require reduced driving speeds and reduced rates of acceleration and braking of the vehicles to proceed with safety. Similarly, drivers that are reckless and overly aggressive endanger others, as do drivers that are physically impaired, or impaired by the use of alcohol and drugs that reduce hand-eye coordination. Uncontrolled movements of the vehicles resulting from skidding, fishtailing, sliding, and rolling also require correction by slower speeds, and reduce rates of acceleration and braking. Obstacles in the roads, or oncoming vehicles in the path of a vehicle going forwardly or backwardly need to be avoided. For all of these reasons, and others, there exists a need for partially overriding the manual control of automotive vehicles with temporary and limited automatic controls in circumstances where such conditions exist.
According to the present invention there is provided a hybrid control system for automatic vehicles that supplements, assists, and overrides the manually operated driver controls where required by traffic laws or by adverse circumstances that present a danger to the driver and to the other vehicle occupants. The system includes a plurality of sensors that detect the traffic laws and regulations as the vehicle proceeds from location to location, as well as detecting various movements and conditions of the vehicle in relation to the roadway, and to other vehicles, and to the surrounding environment, to automatically override the manual controls and take over the control of the vehicle on a temporary basis, and in a limited manner as is required for safety purposes. Among others, the sensors detect the tractive condition of the road with respect to the vehicle, as well as the driver""s vision of the surroundings, such as at nighttime, or during periods of rain, snow, sleet, or fog. These detected conditions are employed to automatically reduce the maximum speed of the vehicle below the prevalent speed limit, and to reduce the ability of the vehicle to accelerate below that normally provided by the vehicle. This partial overriding of the driver""s normally available maximum speed limit and limitation of its acceleration rate are provided to bring the vehicle operation into compliance with the traffic laws, and to better compensate for the adverse conditions detected by the various sensors.